Resistance
Resistance was a combat statistic that mitigated incoming magic damage and effects. Magic spells from the following five schools could be resisted from magical resistance: Fire, Frost, Arcane, Nature, and Shadow. There was no resistance stat for Holy, and as such no players nor NPCs could resist Holy spells. A character's current resistance score to each school was advertised on the character sheet. In PvE, resistance was highly situational and was typically only needed for certain boss encounters. The first one of this type was , famous for requiring significant fire resistance on all raid members. More recently, in Wrath of the Lich King, was made much easier with Frost resistance gear (although this was not necessary). In PvP, resistance was helpful against spellcasters, although Resilience was generally considered to be a more useful stat when choosing between the two. In Mists of Pandaria Spell resistance (elemental and otherwise) is being removed as a stat and mechanic in Mists of Pandaria according to Ghostcrawler (Greg Street). Ghostcrawler|date=1-Mar-2012 6:00 PM PST}} Ghostcrawler|date=02 Mar 2012 02:00 UTC}} Zarhym later explains that stats being sacrificed to add resistance which was only meaningful in narrow situations was a big part in removing this mechanic from the game. Zarhym|date=3/6/12 12:35 PM}} Effective Resistance and Average Mitigation The effective resistance rating of the target was calculated as follows: effective resistance rating = Rb + max((Lt - Lc) * 5, 0) - min(P, Rb) Rb - target base resistance (as advertised on the character sheet) Lt - target level Lc - caster level P - caster spell penetration In PvE boss fights, the player level was usually equal to or less than the boss level, and no spell penetration was in effect. Therefore, in this situation, it was safe to assume that the player's effective resistance was the same as the base resistance (from the character sheet). Note that this formula rendered level 83 bosses as having 15 magical resistance against level 80 player attacks. The percentage of magical damage that was mitigated on average was calculated by the following equation (note that this has changed in Wrath of the Lich King): Damage reduction percentage = 100% * effective resistance rating / ( K + effective resistance rating ) For level 80 mobs this constant K was 400. For level 83 boss mobs K was believed to be 510. Binary Resist and Non-Binary Resist Spell resistance was the second of two rolls to determine whether or not a spell was resisted. (Spell hit was the first roll.) The spell resistance roll would calculate in one of two different ways: one way for Binary Spells, another way for non-Binary spells. Non-binary spells were spells which only dealt damage (like or ). Binary spells were spells which dealt a debuff (like or ) or, for some other reason, needed to take full effect or no effect at all. For binary spells Resistance reduced the chance for the binary spell to land by a certain percentage. Spell hit would not reduce this chance. It was assumed that this percentage was exactly the damage reduction percentage given above. For non-binary spells Resistance increased the chance to suffer only a fraction of the spell's normal damage. As of Wrath of the Lich King, the possible percentages of damage resisted were weighted in sections of 0%, 10%, 20%, ..., 100% averaging to the same overall damage mitigation. However only the closest three or four sections would ever occur at a given resistance value. This allowed a sufficiently high resistance to guarantee a certain resist percentage, even in the worst case. DoT spells were considered non-binary and the partial resistance calculation was applied on each tick. The probability of an x% resistance was given by the following formula (AR is the average resistance calculated above): P(x) = 50% - 250%*|x - AR| If the probability was less than 0, it could not occur. In Cataclysm Partial resists no longer occur against bosses. In Burning Crusade In The Burning Crusade, the percent resisted had a chance to be 0%, 25%, 50%, 75%, or 100%. Blizzard Official US site |accessdate=2007-09-05}} The probabilities were weighted such that the average damage mitigated worked out to the same percentage as with binary spells. Sources of Resistance Resistance could be obtained from buffs, potions, certain class talents, and gear. Racial abilities no longer granted magical resistance and instead granted a percentage chance to miss, as indicated by the table to the right. This chance to miss was added to the spell hit roll, and would not contribute to the non-binary damage mitigation. Stacking The following list contains sources of resistance and stacking information. Each line will stack with other lines. * Self-only buffs, such as Mage Armor stack freely; * Equipped items and enchants stack freely; * Auras, Shaman totems, raid buffs (e.g. Gift of the Wild, Prayer of Shadow Protection), and do not stack with themselves - only the highest single effect of these will apply; * Elixirs and Flasks providing resistance do not stack with themselves. ;Example: In a group where Mark of the Wild, Aspect of the Wild, and Nature Resistance Totem is active, the group will only receive 130 Nature Resistance (either from the aspect or totem). Effectiveness of Resistance The damage absorbed per point of damage/healing/tanking stat lost decreased as resistance was gained, similar to armor. However guaranteeing a certain resistance percentage could be valuable, especially in fights with a large spike of elemental damage. See also *Formulas:Magical resistance * *Resistance equipment *Racial traits *Spell penetration References External links Category:Attributes Category:Combat Category:Game terms Category:Gameplay Category:Magic schools Category:Resistances Category:Tanking